Studies with the beagle dog as the animal model were conducted on the initial phase of the project to ascertain the myocardial cytoprotective effects and antiarrhy thermic effects of the drug tocainide HCl; and the rapid rewarming effects produced by a radio- frequency (RF) helical coil. Hypothermic studies (using the beagle dogs) were also done to evaluate the effectiveness and safety of the RF coil. The coil proved to be effective and safe with the first five dogs. The heart muscle biopsies were evaluated by election microscopy. Tocainide's antiarrhythermic effect was excellent as viewed clinically and by B.P. and E.C.G. recordings. The second phase of the project using five more beagles to represent control animals will not be done. Results that were obtained with the first five experimental dogs along with the data that was gained for use of the R.F. helical coil does not warrant the need of 5 more dogs to be used as controls. Myocardial biopsy evaluations proved tocainide (oral) to have cytoprotective response as does lidocaine (injectable) with similar membrane stabilization properties. The RF helical coil research has expanded into a new trend of experimentation in which live animals are not necessarily needed. Several important findings come out of this study, one of which being that frozen organ tissue can be rapidly rewarmed to normal body temperature for surgical implantation.